[PATCH 0/7] dma-buf: heaps: Turn heaps into modules
From: Maxime Ripard
Date: Wed Feb 25 2026 - 11:42:22 EST
Hi,
The recent introduction of heaps in the optee driver [1] made possible
the creation of heaps as modules.
It's generally a good idea if possible, including for the already
existing system and CMA heaps.
The system one is pretty trivial, the CMA one is a bit more involved,
especially since we have a call from kernel/dma/contiguous.c to the CMA
heap code. This was solved by turning the logic around and making the
CMA heap call into the contiguous DMA code.
Let me know what you think,
Maxime
1: https://lore.kernel.org/dri-devel/20250911135007.1275833-4-jens.wiklander@xxxxxxxxxx/
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
---
Maxime Ripard (7):
dma: contiguous: Turn heap registration logic around
mm: cma: Export cma_alloc and cma_release
mm: cma: Export cma_get_name
mm: cma: Export dma_contiguous_default_area
dma-buf: heaps: Export mem_accounting parameter
dma-buf: heaps: cma: Turn the heap into a module
dma-buf: heaps: system: Turn the heap into a module
drivers/dma-buf/dma-heap.c | 1 +
drivers/dma-buf/heaps/Kconfig | 4 ++--
drivers/dma-buf/heaps/cma_heap.c | 21 +++++----------------
drivers/dma-buf/heaps/system_heap.c | 5 +++++
include/linux/dma-map-ops.h | 5 +++++
kernel/dma/contiguous.c | 27 +++++++++++++++++++++++++--
mm/cma.c | 3 +++
7 files changed, 46 insertions(+), 20 deletions(-)
---
base-commit: 499a718536dc0e1c1d1b6211847207d58acd9916
change-id: 20260225-dma-buf-heaps-as-modules-1034b3ec9f2a
Best regards,
--
Maxime Ripard <mripard@xxxxxxxxxx>